Blatant insanity or no, I like this a lot. An asspect of their relationship- if you could call it that in something like this, haha- that most people don't want to go into. I like the idea that Hidan would leave him alive, not out of pity or sypathy but simply because he is not a realy mercenary and thus, would not really think to finish it. It implies something almost childish about him that I really like.